The present invention relates to a connector arrangement for connecting two surfaces, particularly with at least one surface on a flexible sheet, and the connector arrangement enables the sheet to be attached to itself, surface to surface.
Various surface connectors are known. They include conventional adhesive surface connections. They include arrangements wherein surfaces are connected to each other by elements on one surface engaging elements on the facing surface. The surfaces are connected together by being pressed together, are releasable by being pulled apart or peeled apart and may be reconnected together by being again pressed together.
A produce known as Velcro is an example of this type of connector, wherein one facing surface is coated with small filament loops and the cooperating facing surface is coated with small filament hooks. When the cooperating surfaces are pressed together, hooks and loops interengage sufficiently to attach the surfaces. The surfaces are separated, by peeling them apart, particularly by bending one flexible surface away from the other while pulling them apart. This separates the engaged hooks and loops.
Other surface connectors include projections or prongs from one surface which project into openings or receptacles on the cooperating facing surface. These connectors too are separated by their surfaces being pulled or peeled apart. The prongs and cooperating receptacles may be of varying size. The invention concerns a connector arrangement where the prongs and receptacles are individually quite small, and are fairly densely distributed over each surface. A large plurality of the connector elements on the cooperating surfaces provides a firm connection between the surfaces. Examples of these connectors are U.S. Pat. Nos. 2,499,898; 3,708,837; and 3,708,833. Connectors on a somewhat larger scale are shown in U.S. Pat. No. 3,126,665 and 4,442,153. Often the prongs or projections and the receptacles for them are not cooperatingly shaped although they do separably attach to one another. On the other hand, some more effective connectors have cooperation in the shape of the prongs or projections and the respective receptacles, as in U.S. Pat. No. 3,126,665. For many small size prongs cooperating with many small size receptacles, see U.S. Pat. Nos. 3,113,803 and 2,499,898.
Conforming the shapes of the receptacles complementary to the external shapes of the prong helps assure that each prong is securely nested in its receptacle, resists separation of the prongs from their receptacles and thus makes a firm connection between them. Such conformance is known from U.S. Pat. No. 3,808,648, particularly FIG. 12.
In all these prior art structures, the cooperating connecting elements are defined on only one of the surfaces of two sheets of material or two surfaces to be connected, but not on the opposite surfaces of the same sheet. The attachment of flexible material to itself along opposite surfaces, through cooperating, different connectors on the single flexible sheet material is known from U.S. Pat. No. 4,442,153. There is no prior arrangement where projections defined on one surface of a sheet would be cooperatingly received in correspondingly shaped receptacles or openings in the opposite surface of the same connecting sheet, allowing the same sheet to be first folded over or rolled over upon itself and then fastened in any relative orientation of one surface with respect to the other or allowing the same sheet to be used either as the projection surface or the cooperating receptacle surface.